UVEPROM
Austin Semiconductor, Inc.
OPERATION
The seven modes of operation for the AS27C256 are listed in Table 1. The read mode requires a single 5V supply.
All inputs are TTL level except for V
PP
during programming (12.75V for FLASHRITE Pulse), and (12V) on A9
for signature mode.
AS27C256
TABLE 1. OPERATION MODES
FUNCTION
(PINS)
E\
G\
V
PP
V
CC
A9
A0
DQ0-DQ7
READ
V
IL
V
IL
X
1
V
CC
X
X
Data Out
OUTPUT
STANDBY PROGRAMMING
DISABLE
V
IL
V
IH
X
1
V
CC
X
X
High-Z
V
IH
X
X
1
V
CC
+/-.3V
X
X
High-Z
V
IL
V
IH
V
PP
V
CC
X
X
Data In
MODE*
VERIFY
V
IH
V
IL
V
PP
V
CC
X
X
Data Out
PROGRAM
SIGNATURE MODE
INHIBIT
V
IL
V
IH
X
V
PP
V
CC
X
X
High-Z
V
ID
2
V
IL
V
CC
V
CC
V
ID
2
V
IH
CODE**
MFG
DEVICE
01h
10h
V
IL
1
2
For normal standby & read operation, VPP is Don't Care X.
V
ID
= 12V +/- .5V
NOTES:
* X can be V
IL
or V
IH
**
Die is AMD. User can program on benchtop programmer by selecting AM27C256 from the device
type selection menu.
AS27C256
Rev. 2.0 7/06
Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
3
AUSTIN [ AUSTIN SEMICONDUCTOR ]
